Усилители мощности моно — Buckeye Amps PURIFI 1ET6525SA

The PURIFI 1ET6525SA Monoblock is a single-channel power amplifier from Buckeye Amps, a company based in the United States. Inside is the Purifi 1ET6525SA, the direct successor to the 1ET400A, which carries over second-generation Eigentakt advances from the larger 1ET9040BA and brings lower noise, lower distortion and more power than the module it replaces. The monoblock sells for USD 925, is built to order in three to four weeks and carries a three-year warranty.

Key specs that matter

Measured at 1 kHz and 1 percent THD, output is 230 W into 8 ohm, 450 W into 4 ohm and 510 W into 2 ohm. Signal-to-noise ratio is 137 dB, frequency response runs from 0 Hz to 80 kHz and THD is 0.0001 percent at 100 W into 4 ohm across 20 Hz to 20 kHz. Three gain settings are selectable. High gives 25 dB, reaching full output into 4 ohm from 2.2 V RMS, Medium gives 20 dB with 3.9 V RMS needed, and Low gives 15 dB with 6.9 V RMS needed, while the corresponding 8 ohm figures are 2.3, 4.0 and 7.1 V RMS. The case is 254 mm wide, 330 mm deep and 89 mm high, with a weight of 3.2 kg.

Engineering and use context

A Hypex SMPS1200A400 switch-mode supply powers the unit, which reaches 94 percent efficiency with an output current capability of 25 A and a very high damping factor. Buckeye fits its own input and output board built around a Texas Instruments OPA1612 op-amp, with TPS7A30 and TPS7A49 low-noise voltage regulators feeding it. Start-up and shutdown are muted and soft. Automatic signal sensing can wake the amplifier and put it back to sleep, and a 12 V trigger input allows remote switching as an alternative. A front LED indicates clipping and error conditions. The all-aluminium enclosure is finished in black powder coat and manufactured in North America by Protocase, and alternative case styles and colours are available as upgrades.

Pairing

The signal input is a Neutrik XLR connector, so the preamplifier or DAC feeding it should offer XLR outputs. The three gain steps let the amplifier reach full output across a wide range of input levels, so the setting can follow the voltage the source stage supplies. Loudspeaker leads connect through five-way binding posts plated in gold, and the amplifier is specified into very low impedance loads. A preamplifier with a trigger output can switch a pair of these monoblocks on together.

Alternatives

The Buckeye PURIFI 1ET9040BA Monoblock is the other Purifi-based mono amplifier in the range, built on the module whose Eigentakt developments fed into the 1ET6525SA.